EDIT: Updated the bracket slightly. Lengthened it by 1mm to accommodate a washer between the coupler and the bearing, and widened it slightly for better alignment with the stepper motor screws.
This is an update to my Z support for the Prusa Mendel I2. Unlike the previous version, these should fit all I2 Prusas without any modification to the source model.
I have a video on YouTube that covers the design and, although a bit long, I cover a few things about assembling this that will save you some time and make things go together easy.
I think something like this should be included in the original design, Z creep is a problem that is completely solved by this.
YouTube video linked below. If you build this for your printer, let me know how it works for you and/or post a pic here under the "I made one" area.